Species loss revisited

Among his books are The Economics of Population Growth; Effort, Opportunity, and Wealth;and Population Matters: People, Resources, Environment, and Immigration (the latter was published by Transaction).     

Using the Delphi process to analyze social policy implementation: A post hoc case from vocational rehabilitation

This study uses a Policy Delphi to discern differences in perspective among and within groups responsible for formulating and implementing vocational rehabilitation policy. Four groups of players were chosen for our analysis: government officials, academics, directors of rehabilitation centers, and the staff who interface with program participants. Significant differences were found between the groups regarding the relative importance of possible legislative goals. This suggests that the failure of vocational rehabilitation policy to promote a work agenda may be attributed to a lack of consensus among policy implementors. The Delphi technique could help policy planners understand the different perspectives within the implementation community, and hence craft more realistic legislation.     

Estimation and Inference Are Missing Data Problems: Unifying Social Science Statistics via Bayesian Simulation

Bayesian simulation is increasingly exploited in the socialsciences for estimation and inference of model parameters. Butan especially useful (if often overlooked) feature of Bayesiansimulation is that it can be used to estimate any function ofmodel parameters, including "auxiliary" quantities such as goodness-of-fitstatistics, predicted values, and residuals. Bayesian simulationtreats these quantities as if they were missing data, samplingfrom their implied posterior densities. Exploiting this principlealso lets researchers estimate models via Bayesian simulationwhere maximum-likelihood estimation would be intractable. Bayesiansimulation thus provides a unified solution for quantitativesocial science. I elaborate these ideas in a variety of contexts:these include generalized linear models for binary responsesusing data on bill cosponsorship recently reanalyzed in PoliticalAnalysis, item—response models for the measurement ofrespondent's levels of political information in public opinionsurveys, the estimation and analysis of legislators' ideal pointsfrom roll-call data, and outlier-resistant regression estimatesof incumbency advantage in U.S. Congressional elections     

Selection Bias in Comparative Research: The Case of Incomplete Data Sets

Selection bias is an important but often neglected problem incomparative research. While comparative case studies pay someattention to this problem, this is less the case in broadercross-national studies, where this problem may appear throughthe way the data used are generated. The article discusses threeexamples: studies of the success of newly formed political parties,research on protest events, and recent work on ethnic conflict.In all cases the data at hand are likely to be afflicted byselection bias. Failing to take into consideration this problemleads to serious biases in the estimation of simple relationships.Empirical examples illustrate a possible solution (a variationof a Tobit model) to the problems in these cases. The articlealso discusses results of Monte Carlo simulations, illustratingunder what conditions the proposed estimation procedures leadto improved results.     

The use of the Foster & Freeman Fx5 Fibre Finder in forensic textile examinations.

The Fx5 Fibre Finder has been developed by Foster & Freeman Ltd to automatically search tape lifts for coloured fibres specified by the operator. Experiments and casework studies have been conducted to assess primarily the performance of the instrument but also, where possible, to compare it with manual searching. Tape lifts have always been manually searched at this laboratory and it is a laborious task. The use of a machine such as the Fx5 would release a scientist from many hours of low power microscopy to be free for other duties and therefore could be a valuable labour saving device in forensic textile examination.     

Politische Orientierungen gewerkschaftlich organisierter Arbeiter- und Mittelschichten in der Schweiz

Das Thema dieser Studie sind die politischen Einstellungen von ge-werkschaftlich organisierten Arbeitnehmerinnen und Arbeitnehmern in der Schweiz. Anhand von Daten einer repräsentativen Befragung von Mitgliedern von drei schweizerischen Gewerkschaften (GBI, SMUV, VPOD) und eines Angestelltenverbandes (VSAM) wird im folgenden dokumentiert, dass die "traditionelle" Arbeiterschicht, die "sozialkulturellen Spezialisten" sowie die "Technokraten" und "Manager" jeweils unterschiedliche politische Orientierungen vertreten. Während die Arbeiter für "klassisch" linke, sozialdemokratische und eher materialistische politische Positionen einstehen, sind die gewerkschaftlich organisierten "sozialkulturellen Spezialisten" in der Mittelschicht deutlich linker und postmaterialistischer und die ebenfalls der Mittelschicht zuzurechnenden "Technokraten" und "Manager" eher bürgerlich und materialistischer eingestellt. Insgesamt lassen sich weder für die These einer Entpolitisierung noch für die These einer Konvergenz der politischen Orientierungen eindeutige Hinweise finden. Vielmehr ist die gewerkschaftlich organisierte Arbeitnehmerschaft in der Schweiz politisch heterogen. Diese Heterogenität wiederum reduziert die Macht und Einflusschancen der schweizerischen Gewerkschaftsbewegung.